Unfortunately, no. There is no absolute truth in measurement. Measurement is really about probability. The percentages of times the measurement will be different are the uncertainties of that parameter. What we are left with is “close enough” or, the nearest we can currently get with the technologies and equipment available. Fortunately, for most applications, close enough is good enough. So long as measurements are standardized and communicated internationally—by our National Measurement Institutes (NMIs) like NIST,1 PTB,2 NPL,3 etc.—we have a global “mother tongue” of accuracy. But a shared language does no good unless it is applied. This is the goal of traceability. Traceability is what allows us to use international standards as the references for calibrating measurement instruments, so that mètre, even when called a “meter,” is still the same length.
From: Beyond NIST-Traceability: What Really Creates Accuracy